There is a known medical wire that is provided with a main wire-strand portion provided over the entire length thereof in a longitudinal direction and a sub wire-strand portion that is secured to the main wire-strand portion at a portion of the main wire-strand portion in the longitudinal direction, and that has a first region having a relatively small lateral cross-sectional area and a second region having a lateral cross-sectional area that is greater than that of the first region (for example, see Patent Literature 1).
Because the medical wire of Patent Literature 1 is not a wire in which two types of wires having different rigidities are arranged next to each other in a longitudinal direction and are joined by means of welding or the like, there is no stress concentration at join sites, and thus, it is possible to prevent deterioration of the strength at the join sites, and the medical wire exhibits excellent performance in that it is possible, even in medical equipment provided with a flexible inserted portion, to suitably generate a desired driving force on the distal-end side thereof.